/**
 * 
 */
package at.gv.egiz.pdfas.impl.input;

import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;

import at.gv.egiz.pdfas.framework.input.TextDataSource;

/**
 * A TextDataSource that keeps the text in memory.
 * 
 * <p>
 * Keeping the text in memory is fast as long as the text is short, but may
 * result in bad memory performance when the text is longer. Use a FileBased
 * TextDataSource instead if memory is an issue.
 * </p>
 * 
 * @author wprinz
 */
public class TextDataSourceImpl implements TextDataSource
{
  /**
   * The text.
   */
  protected String text = null;
  
  private final static String CHARSET = "UTF-8";

  /**
   * Constructor that sets the text.
   * 
   * @param text
   *          The text.
   */
  public TextDataSourceImpl(String text)
  {
    this.text = text;
  }

  /**
   * @see at.gv.egiz.pdfas.framework.input.TextDataSource#getText()
   */
  public String getText()
  {
    return this.text;
  }

  /**
   * @see at.gv.egiz.pdfas.framework.input.DataSource#createInputStream()
   */
  public InputStream createInputStream()
  {
    try
    {
      byte[] data = getText().getBytes(CHARSET);
      // PERF: if memory is an issue (e.g. in web), use a FileBased TextDataSource instead.
      return new ByteArrayInputStream(data);
    }
    catch (UnsupportedEncodingException e)
    {
      throw new RuntimeException(e);
    }
  }

  /**
   * @see at.gv.egiz.pdfas.framework.input.DataSource#getLength()
   */
  public int getLength()
  {
    try
    {
      byte[] data = getText().getBytes(CHARSET);
      return data.length;
    }
    catch (UnsupportedEncodingException e)
    {
      throw new RuntimeException(e);
    }
  }

  /**
   * @see at.gv.egiz.pdfas.framework.input.DataSource#getAsByteArray()
   */
  public byte[] getAsByteArray()
  {
    try
    {
      byte[] data = getText().getBytes(CHARSET);
      return data;
    }
    catch (UnsupportedEncodingException e)
    {
      throw new RuntimeException(e);
    }
  }

}